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VHF installation questions
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Captain B
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First recorded activity by BoatBanter: Jul 2006
Posts: 12
VHF installation questions
wrote:
Sorry Chuck, but with frequency modulation (used with marine VHF
radios), the 'loudness' of a received signal has *nothing to do* with
the transmitter's power output or quality of the antenna system. Asking
"can you hear me now?" of a fellow mariner in the same harbor seems a
dubious way of checking the integrity of a vital communications system.
The most likely failure mechanism for an 'old' coax is water migration
into the cable - which generally happens at the antenna connection.
This *will* change the impedance of the cable, which *will* show up on
the thruline, or VSWR meter. "Old coax" in and of itself usually
doesn't "become lossy" simply becuase of it's age; 100 year old copper
conducts just as freely as 'new' copper.
MW
chuck wrote:
I don't think Roger is too interested in measurements, though, and
there is a lot of wisdom in the notion that if you want to know if
your big VHF is louder than your handheld VHF, the best way to find out
is to see if it IS louder. ;-)
I agree with MW, even pick a few marinas at nearby ports and see how
far away you can hail them from! It just sounds like from a time
standpoint, you could get a simple answer this way the fastest.
Assuming all works acceptable, after the cruise, break out the meters
and get technical. A lot of these users have great ideas for you.
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